Multilayer sheet comprising fabric and resin, travel bag case made therefrom, and apparatus for manufacturing same

ABSTRACT

According to the present invention, in some embodiments, since a first resin, a first fabric and a second resin are layered and coupled to each other and the first resin and the second resin are coupled by through-holes of the first fabric, the first resin and the second resin are uniformly absorbed and coated on the surface of the first fabric, and the first resin, the first fabric, and the second resin are closely coupled to each other, thereby enabling a unique color of the first fabric to be displayed on the exterior, a travel bag having very excellent compactness, tensile strength and impact strength to be manufactured, a travel bag having excellent quality to be provided even if manufacturing costs and manufacturing processes are decreased, and a travel bag capable of maximizing user convenience and the operability of the travel bag by remarkably reducing the weight to be provided.

TECHNICAL FIELD

The present disclosure relates to a multilayer sheet, a case of a travelbag, and a method for manufacturing the same. More particularly, thepresent disclosure relates to a multilayer sheet constituting a rawmaterial of a case of a travel bag in which articles are contained, acase configured by press-molding such a multilayer sheet, and a casemanufacturing device.

BACKGROUND ART

Travel bags are used to store and protect articles for travel. Commonlyused travel bags have casters and handles installed thereon. Travel bagsare largely classified into hard cases and soft cases according to thematerial of the bag body (case).

Most soft cases are made of chemical fibers such as nylon, polyester,and the like, and have wires formed along the corners of the bag body inorder to maintain the shape. Soft case travel bags have a drawback inthat, if a wire is bent by an external impact, it is impossible torestore the same to the original condition.

Hard cases are the most prevalent type of cases on the current market.The bag body (case) itself is made of hard plastic such that the samecan maintain the shape without a skeleton structure such as a wire. Thebag body is both hard and elastic, thereby having an excellent functionof protecting objects contained therein.

However, most conventional hard cases have a problem in that edges orcorners thereof will be broken or recessed inward by impacts applied tothe cases beyond the threshold of elastic restoration when the casesfall down or drop during a use or during a transportation whilecontaining users' luggage. In such a case, restoration is practicallyimpossible, and, even if restored, traces of fracture such as whitelines or wrinkle marks are left permanently. Therefore, it hasconstantly been requested to develop a travel bag, the durability ofwhich can be improved while allowing elastic deformation.

Meanwhile, Korean Registered Patent No. 10-1189901 (Registration Date:Oct. 4, 2012) discloses a feature wherein a polypropylene resincomposition is used to manufacture a travel bag. However, it is stillrequested to develop a travel bag having a new structure, in order tomanufacture a hard case-type travel bag, the strength of which can beimproved further.

DETAILED DESCRIPTION OF THE INVENTION Technical Problem

An aspect of the present disclosure is to provide a multilayer sheet, acase of a travel bag, and a case manufacturing device for manufacturingthe same, wherein a fabric constituting the case of a travel bag and aplurality of layers made of thermoplastic resin, laminated on thefabric, are tightly laminated, thereby improving elasticity anddurability, and the type of weaving of the fabric and the colorimpression thereof are naturally exposed to the outside while protectingthe fabric.

Another aspect of the present disclosure is to provide a multilayersheet, a case of a travel bag, and a case manufacturing device formanufacturing the same, wherein, compared with conventional travel bagsmade of polycarbonate (PC), acrylonitrile butadiene styrene (BS),polypropylene (PP), and the like, the rigidity and durability can beimproved while reducing the manufacturing cost and decreasing theweight.

Technical Solution

In accordance with an aspect of the present disclosure, there isprovided a multilayer sheet constituting a case of a travel bag, theshape of which is made through plastic working such that articles arecontained therein, the multilayer sheet having elastically restoringpower and including: a first fabric that includes a fabric configured bycoupling of fibers and has multiple through-holes penetrating thefabric; a first resin laminated on the first fabric and absorbed andcoated on a surface of the first fabric; and a second resin laminated onthe first fabric from a side opposite to the first resin, absorbed andcoated on the surface of the first fabric, and coupled to the firstresin via the through-holes.

The multilayer sheet according to the present disclosure may include: asecond fabric that includes a fabric configured by coupling of fibersand has multiple through-holes penetrating the fabric, the second fabricbeing laminated on the first resin from a side opposite to the firstfabric; and a third fabric that includes a fabric configured by couplingof fibers and has multiple through-holes penetrating the fabric, thethird fabric being laminated on the second resin from the side oppositeto the first fabric.

In connection with the multilayer sheet according to the presentdisclosure, the first fabric may be made of a woven material, the firstfabric, the first resin, and the second resin may be made ofpolypropylene, and at least one of the first resin and the second resinmay be configured to be transparent.

According to the present disclosure, the through-holes may have a widthof 0.5-20 mm.

In accordance with another aspect of the present disclosure, there isprovided a case of a travel bag including the above-mentioned multilayersheet configured by press working.

In accordance with another aspect of the present disclosure, there isprovided a case manufacturing device for manufacturing a case of atravel bag, the shape of which is made through plastic working such thatarticles are contained therein, the travel bag having elasticallyrestoring power, the case manufacturing device including: a first fabricsupply portion configured to continuously supply a first fabric thatincludes a fabric configured by coupling of fibers and has multiplethrough-holes penetrating the fabric; a first resin supply portionconfigured to continuously supply a molten first resin in a directlydownward direction; a first roller and a second roller rotating inopposite directions while constituting a pair such that the first fabricand the first resin pass between the first roller and the second rollerand become laminated on each other; a second resin supply portionconfigured to continuously supply a molten second resin in a directlydownward direction; and a third roller and a fourth roller rotating inopposite directions while constituting a pair such that the first resin,the first fabric, and the second resin pass between the third roller andthe fourth roller and become laminated successively, thereby couplingand combining the first resin and the second resin via thethrough-holes.

The first roller may be configured to directly contact the first resin;the second roller may be configured to directly contact the firstfabric; the third roller may be configured to directly contact the firstresin laminated on the first fabric; the fourth roller is configured todirectly contact the second resin; and the first roller, the secondroller, the third roller, and the fourth roller may be continuouslyarranged in a row.

The case manufacturing device according to the present disclosure mayfurther include a fifth roller arranged adjacent to the fourth rollerand configured to rotate in the opposite direction to the fourth roller.The surface temperature of the second roller may be higher than thesurface temperature of the first roller. The surface temperature of thethird roller and the fourth roller may be higher than the surface of thesecond roller. The surface temperature of the fifth roller may be higherthan the surface temperature of the third roller and the fourth roller.

The case manufacturing device according to the present disclosure mayfurther include a second fabric supply portion configured tocontinuously supply a second fabric that includes a fabric configured bycoupling of fibers and has multiple through-holes penetrating thefabric. The first roller and the second roller may be configured suchthat the second fabric, the first resin, and the first fabric passbetween the first roller and the second roller and become laminatedsuccessively.

The case manufacturing device according to the present disclosure mayfurther include a third fabric supply portion configured to continuouslysupply a third fabric that includes a fabric configured by coupling offibers and has multiple through-holes penetrating the fabric. Thirdroller and the fourth roller may be configured such that the secondfabric, the first resin, the first fabric, the second resin, and thethird fabric between the third roller and the fourth roller and becomelaminated successively.

The case manufacturing device according to the present disclosure mayinclude: a sheet clamp configured to hold an edge of a multilayer sheetincluding the first resin, the first fabric, and the second resin afterpassing through the third roller and the fourth roller; a preheaterhaving multiple slots into which the sheet clamp is inserted, thepreheater being configured such that a hot wind is supplied andcirculated therein; and a molding machine configured to press-work themultilayer sheet preheated through the preheater. The slots may bearranged to be spaced apart from each other in a leftward/rightwarddirection.

Advantageous Effects

As described above, according to the present disclosure, the multilayersheet includes a first resin, a first fabric, and a second resin. Thefirst resin, the first fabric, and the second resin are made ofpolypropylene. The first resin and/or the second resin are configured tobe transparent. Accordingly, the first fabric, the first resin, and thesecond resin can be coupled tightly, and the compactness and strength ofthe multilayer sheet can be maximized. The unique color of the firstfabric can be seen from the outside through the first resin and/or thesecond resin, making it unnecessary to mix or apply a master batch in anormal extrusion type such that a color is exhibited.

Moreover, according to the present disclosure, the first fabric ispositioned at the center of the multilayer sheet, and the first resinand the second resin are coated and positioned on both sides of thefirst fabric. This advantageously increases the tensile strength andimpact strength of the entire multilayer sheet to a large extent. Inaddition, when the first resin and/or the second resin are configured tobe transparent, the aesthetic appearance unique to the first fabric (thetexture type, pattern, and the like specific to the fabric resultingfrom interweaving of a warp and a weft) and the naturalness thereof canbe directly seen from and embedded in the case. It is also possible toprovide a travel bag with an excellent quality even if the manufacturingcost and manufacturing process are reduced.

In addition, according to the present disclosure, the first resin, thefirst fabric, and the second resin are all made of the samepolypropylene such that, compared with conventional travel bags made ofpolycarbonate (PC), acrylonitrile butadiene styrene (ABS), and the like,the product price can be reduced substantially, there is no need to adda separate impact resistance enhancer in order to increase the impactstrength and the tensile strength, and no master batch needs to beapplied. This provides a substantial advantage in terms of massproduction and industrial applicability, and, since the weight can bereduced substantially, the user convenience and bag operability(mobility or the like) can be maximized.

Moreover, according to the present disclosure, the multilayer sheet hasa first fabric positioned between the first resin and the second resin,thereby constituting a multilayered structure. This substantially lowersthe possibility that the multilayer sheet or the case will be torn by anexternal impact. In addition, the excellent elastically restoring powerguarantees that, even if creased or recessed, the same can instantlyreturn to the original condition. Furthermore, the possibility thatwhitening marks will be famed can be reduced substantially.

In addition, according to the present disclosure, it is possible toprovide a case manufacturing device capable of manufacturing amultilayer sheet and a case of a travel bag, which have very excellentcompactness, tensile strength, and impact strength.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a travel bag according to the presentdisclosure;

FIG. 2 schematically illustrates a partial configuration of a casemanufacturing device according to the present disclosure;

FIG. 3 is an exploded perspective view schematically illustrating amultilayer sheet according to the present disclosure;

FIG. 4 schematically illustrates a partial configuration of a casemanufacturing device according to another embodiment of the presentdisclosure;

FIG. 5 is an exploded perspective view schematically illustrating amultilayer sheet according to another embodiment of the presentdisclosure;

FIG. 6 is an exploded perspective view schematically illustrating amultilayer sheet according to still another embodiment of the presentdisclosure;

FIG. 7 schematically illustrates a partial configuration of a casemanufacturing device according to the present disclosure;

FIG. 8 is a photograph of a travel bag according to the presentdisclosure; and

FIG. 9 is a magnified photograph of the surface of the case of thetravel bag illustrated in FIG. 8.

MODE FOR CARRYING OUT THE INVENTION

Hereinafter, preferred embodiments of the present disclosure will bedescribed in detail with reference to the accompanying drawings. It isto be noted, however, that, in describing the present disclosure,detailed descriptions of already known functions or configurations willbe omitted to clarify the gist of the present disclosure.

FIG. 1 is a perspective view of a travel bag 1 according to the presentdisclosure. FIG. 2 schematically illustrates a partial configuration ofa case manufacturing device 100 according to the present disclosure.FIG. 3 is an exploded perspective view schematically illustrating amultilayer sheet 3 according to the present disclosure.

It is to be noted that, although the multilayer sheet 3 is expressed inline type in FIG. 2, the multilayer sheet 3 has a width in a directionparallel with the rotating shafts 311, 321, 331, 341, and 351 ofrespective rollers 310, 320, 330, 340, and 350.

FIG. 3 is for the purpose of illustrating the laminated configuration ofthe multilayer sheet 3. The first fabric 10, the first resin 20, and thesecond resin 30 may have forms different from those illustrated in FIG.3, and may also have sizes larger than those illustrated in FIG. 3.

The case 2 of the travel bag 1 according to the present disclosure(hereinafter, simply referred to as the case 2) is shaped such thatarticles can be contained therein. As illustrated in FIG. 1, a handle 4,casters 5, and the like may be coupled to the case 2, therebyconfiguring a travel bag 1 in a complete form.

The case 2 may have various foams and sizes as long as articles can becontained therein. As in the case of a conventional travel bag, the case2 may include two separate parts, the edges of which are coupled to eachother by a zipper or the like. In this case, the two parts of the case2, constituting a pair, are separately manufactured and then assembled.

As will be described later, a pre-molded multilayer sheet 3 is subjectedto plastic working through plastic molding such that the form of thecase 2 is made. The multilayer sheet 3 is configured in a flat platetype, and the case 2 is variously shaped to be curved or bent accordingto the mold for pressing molding.

The basic structure of the multilayer sheet 3 according to the presentdisclosure will now be described.

The multilayer sheet 3 according to the present disclosure refers to amultilayer sheet 3 that constitutes the case 2 of a travel bag in whicharticles are contained. The multilayer sheet 3 basically includes afirst fabric 10, a first resin 20, and a second resin 30.

The first fabric 10 is famed by coupling of fibers, and has multiplethrough-holes 13 that penetrate the fabric. Particularly, the firstfabric 10 is configured in a thin cloth type and has through-holes 13that penetrate the same from one surface to the other surface thereof.Such through-holes 13 are repeatedly arranged throughout the entire areaof the first fabric 10.

The first fabric 10 according to the present disclosure may be made of awoven material, a knitted material, a non-woven fabric, or a combinationthereof. Particularly, the first fabric 10 is preferably made of a wovenmaterial.

When the first fabric 10 is made of a woven material, a warp 11 (thewarp 11 itself may be made of a combination of multiple fiber strands)and a weft 12 (the weft 12 itself may be made of a combination ofmultiple fiber strands) are woven to repeatedly intersect one above theother, as fibers that constitute the first fabric 10. Accordingly, thewarp 11 and the weft 12 foam a lattice shape, which is repeatedlypenetrated by holes (through-holes 13).

In this case, the width of the through-holes 13 (the length of one sideof each through-hole when the first fabric 10 constitutes a lattice) maybe 0.5-20 mm. Particularly, the width is preferably 1-3 mm.

The first fabric 10 may be made of a natural fiber, a synthetic fiber,or a combination thereof, but is preferably made of a synthetic fiber.Particularly, the first fabric 10 is made of a polypropylene fiber.

The first resin 20 is laminated on the first fiber 10 from one sidesurface of the first fabric 10, and is forced against and coupled to thefirst fabric 10.

The first resin 20 may be made of a thermoplastic resin. Particularly,the first resin 20 is preferably made of polypropylene. The first resin20, made of the same material as that of the first fabric 10 as such,can be coupled to the first fabric 10 more tightly. According to thepresent disclosure, furthermore, the first fabric 10 is made of acombination of multiple fibers such that particles of the first resin 20infiltrate between fiber strands that constitute the first fabric 10,thereby resulting in film coupling between the two.

Meanwhile, the first resin 20 may be configured to be transparent.

The second resin 30 is laminated on the first fiber 10 from the oppositeside of the first resin 20, and is forced against and coupled to thefirst fabric 10. In this case, the first resin 20 and the second resin30 are coupled to each other via the through-holes 13 of the firstfabric 10.

The second resin 30 may be made of a thermoplastic resin and,particularly, is preferably made of polypropylene. The second resin 30,made of the same material as that of the first fabric 10 and that of thefirst resin 20 as such, can be coupled to the first fabric 10 and to thefirst resin 20 more tightly. According to the present disclosure,furthermore, the first fabric 10 is made of a combination of multiplefibers such that particles of the second resin 30 infiltrate betweenfiber strands that constitute the first fabric 10, thereby resulting infirm coupling between the two. Moreover, the second resin 30 contactsand is coupled to the first resin 20 via the through-holes of the firstfabric 10 such that the first resin 20, the first fabric 10, and thesecond resin 30 are coupled in a very stable and robust manner.

Meanwhile, the second resin 30 may be configured to be transparent.

As described above, the multilayer sheet 3 according to the presentdisclosure has the following advantages. The same includes a first resin20, a first fabric 10, and a second resin 30. The first resin 20, thefirst fabric 10, and the second resin 30 are made of polypropylene. Thefirst resin 20 and/or the second resin 30 are configured to betransparent. Accordingly, the first fabric 10, the first resin 20, andthe second resin 30 can be coupled tightly, and the compactness andstrength of the multilayer sheet 3 can be maximized. The unique color ofthe first fabric 10 appears through the first resin 20 and/or the secondresin 30, making it unnecessary to mix or apply a master batch in anormal extrusion type such that a color is exhibited.

Moreover, the first fabric 10 is positioned at the center of themultilayer sheet 3, and the first resin 20 and the second resin 30 arecoated and positioned on both sides of the first fabric 10. Thisadvantageously increases the tensile strength and impact strength of theentire multilayer sheet 3 to a large extent. In addition, when the firstresin 20 and/or the second resin 30 are configured to be transparent,the aesthetic appearance unique to the first fabric 10 (the texturetype, pattern, and the like specific to the fabric resulting frominterweaving of a warp and a weft) and the naturalness thereof can bedirectly seen from and embedded in the case. It is also possible toprovide a travel bag with a high quality even if the manufacturing costand manufacturing process are reduced.

In addition, the first resin 20, the first fabric 10, and the secondresin 30 are all made of the same polypropylene such that, compared withconventional travel bags simply made of polycarbonate (PC),acrylonitrile butadiene styrene (ABS), and the like, the product pricecan be reduced substantially, there is no need to add a separate impactresistance enhancer in order to increase the impact strength and tensilestrength, and no master batch needs to be applied. This provides asubstantial advantage in tams of mass production and industrialapplicability, and, since the weight can be reduced substantially, theuser convenience and bag operability (mobility or the like) can bemaximized.

Moreover, conventional travel bags made of PC and the like have aproblem in that the same are easily creased, torn, or recessed byimpacts and are then impossible to restore. Even if restored, traces offracture such as white lines (whitening) or crease marks are leftpermanently. In contrast, the multilayer sheet 3 according to thepresent disclosure has a first fabric 10 positioned between the firstresin 20 and the second resin 30, thereby constituting a multilayeredstructure. This substantially lowers the possibility that the multilayersheet 3 or the case will be torn by an external impact. In addition, theexcellent elastically restoring power guarantees that, even if creasedor recessed, the same can instantly return to the original condition.Furthermore, the possibility that whitening marks will be famed can bereduced substantially.

The multilayer sheet 3 according to the present disclosure may solelyinclude a first fabric 10, a first resin 20, and a second resin 30 asillustrated in FIG. 3. The multilayer sheet 3 may further include asecond fabric 40 and/or a third fabric 50 as illustrated in FIG. 5 andFIG. 6. Alternatively, the multilayer sheet 3 may further include aseparate resin layer 60.

The case manufacturing device 100 according to the present disclosure isa device for manufacturing a case 2 finally. The above-mentionedmultilayer sheet 3 is also made in the process of manufacturing a case 2by the case manufacturing device 100.

The case manufacturing device 100 includes a first fabric supply portion110, a first resin supply portion 210, a first roller 310, a secondroller 320, a second resin supply portion 220, a third roller 330, and afourth roller 340. In addition, the case manufacturing device 100 mayfurther include a fifth roller 350.

The first fabric supply portion 110 is configured to continuously supplya first fabric 10.

The first fabric 10 is manufactured in a fabric type and supplied to thecase manufacturing device 100 according to the present disclosure. Itcould be understood that a separate drum may be provided before thefirst fabric supply portion 110 such that the first fabric 10 is woundaround the same.

The first fabric 10 supplied from the first fabric supply portion 110 iscontinuously supplied between the first roller 310 and the second roller320, and is particularly supplied such that the same is forced againstthe outer peripheral surface of the second roller 320.

The first resin supply portion 210 is configured in an extruder type anddischarges a first resin 20, which has been heated and melted, in thedirectly downward direction such that the discharged first resin 20 issupplied between the first roller 310 and the second roller 320. Thefirst resin supply portion 210 has a nozzle positioned right above theboundary between the first roller 310 and the second roller 320 suchthat the first resin 20, which is discharged through the nozzle of thefirst resin supply portion 210, is provided by gravity between the firstroller 310 and the second roller 320.

The first resin supply portion 210 may be configured to have apredetermined width in a direction parallel with the rotating shafts311, 321, 331, 341, and 351 of respective rollers 310, 320, 330, 340,and 350, and the nozzle of the first resin supply portion 210 may alsobe configured to have a predetermined width in a direction parallel withthe rotating shafts 311, 321, 331, 341, and 351 of respective rollers310, 320, 330, 340, and 350.

The first roller 310 and the second roller 320 are configured inconventional roller types, constitute a pair, and rotate in the oppositedirections. The rotating shaft 311 of the first roller 310 and therotating shaft 321 of the second roller 320 are parallel with eachother. When the first roller 310 rotates clockwise with reference toFIG. 2, the second roller 320 rotates counterclockwise.

The first roller 310 and the second roller 320 are not completely forcedagainst each other, but are spaced apart such that a predetermined gapis formed therebetween. The first fabric 10 and the first resin 20 arelaminated on each other and pass through the gap, thereby being coupledto each other.

Assuming that the thickness of the first resin 20 discharged from thenozzle of the first resin supply portion 210 if t1, the thickness of thefirst fabric 10 supplied from the first fabric supply portion 110 is t2,and the gap between the first roller 310 and the second roller 320 ist3, t3 is preferably smaller than the sum of t1 and t2.

In addition, the case manufacturing device 100 according to the presentdisclosure is configured such that the first resin 20 directly contactsthe first roller 310, and the first fabric 10 directly contacts thesecond roller 320. The first resin 20 and the first fabric 10 arecoupled to each other while passing through the gap between the firstroller 310 and the second roller 320, and are forced against the outerperipheral surface of the second roller 320 in a predetermined range.

The second resin supply portion 220 is configured in an extruder typeand discharges a second resin 30, which has been heated and melted, inthe directly downward direction such that the discharged second resin 30is supplied between the third roller 330 and the fourth roller 340. Thesecond resin supply portion 220 has a nozzle positioned right above theboundary between the third roller 330 and the fourth roller 340 suchthat the second resin 30, which is discharged through the nozzle of thesecond resin supply portion 220, is provided by gravity between thethird roller 330 and the fourth roller 340.

The second resin supply portion 220 may be configured to have apredetermined width in a direction parallel with the rotating shafts311, 321, 331, 341, and 351 of respective rollers 310, 320, 330, 340,and 350, and the nozzle of the second resin supply portion 220 may alsobe configured to have a predetermined width in a direction parallel withthe rotating shafts 311, 321, 331, 341, and 351 of respective rollers310, 320, 330, 340, and 350.

The third roller 330 and the fourth roller 340 are configured inconventional roller types, constitute a pair, and rotate in the oppositedirections. The rotating shaft 331 of the third roller 330 and therotating shaft 341 of the fourth roller 340 are parallel with eachother. When the third roller 330 rotates clockwise with reference toFIG. 2, the fourth roller 340 rotates counterclockwise.

The third roller 330 and the fourth roller 340 are not completely forcedagainst each other, but are spaced apart such that a predetermined gapis famed therebetween. The second resin 30 is additionally laminated onthe first resin 20 and the first fabric 10, which have been laminated oneach other, while passing through the gap and thus become coupled toeach other.

Assuming that the thickness of the first resin 20 discharged from thenozzle of the first resin supply portion 210 is t1, the thickness of thefirst fabric 10 supplied from the first fabric supply portion 110 is t2,the thickness of the second resin 30 discharged from the nozzle of thesecond resin supply portion 220 is t4, and the gap between the thirdroller 330 and the fourth roller 340 is t5, t5 is preferably smallerthan the sum of t1, t2, and t4.

In addition, the case manufacturing device 100 according to the presentdisclosure is configured such that the first resin 20 coupled to thefirst fabric 10 directly contacts the third roller 330, and the secondresin 30 directly contacts the fourth roller 340. The first resin 20,the first fabric 10, and the second resin 30 are coupled to one anotherwhile passing through the gap between the third roller 330 and thefourth roller 340, and are forced against the outer peripheral surfaceof the fourth roller 340 in a predetermined range.

Moreover, the first resin 20, the first fabric 10, and the second resin30 are successively laminated while passing through the third roller 330and the fourth roller 340. In this process, the first resin 20 and thesecond resin 30 are strongly coupled to each other via the through-holes13 of the first fabric 10.

As illustrated in FIG. 2, in connection with the case manufacturingdevice 100 according to the present disclosure, the first roller 310,the second roller 320, the third roller 330, and the fourth roller 340are preferably arranged continuously in a row.

In this case, the first resin 20 and the first fabric 10, which havebeen laminated on each other, pass between the second roller 320 and thethird roller 330, and the gap between the second roller 320 and thethird roller 330 is preferably larger than or equal to the gap betweenthe first roller 310 and the second roller 320.

The fifth roller 350 is configured in a conventional roller type and isarranged adjacent to the fourth roller 340 so as to rotate in theopposite direction to that of the fourth roller 340. The rotating shaft351 of the fifth roller 350 and the rotating shaft 341 of the fourthroller 340 are parallel with each other. When the fourth roller 340rotates counterclockwise with reference to FIG. 2, the fifth roller 350rotates clockwise.

In connection with the case manufacturing device 100 according to thepresent disclosure, the first roller 310, the second roller 320, thethird roller 330, the fourth roller 340, and the fifth roller 350 arepreferably arranged continuously in a row. Provision of the fifth roller350 guarantees that the first resin 20, the first fabric 10, and thesecond resin 330, which have been laminated on one another, aresufficiently forced against the outer peripheral surface of the fourthroller 340. In this process, the first resin 20, the first fabric 10,and the second resin 30 are tightly couple to one another.

In connection with the case manufacturing device 100 according to thepresent disclosure, respective surfaces of the first roller 310, thesecond roller 320, the third roller 330, the fourth roller 340, and thefifth roller 350 are preferably heated such that each can maintain apredetermined level of temperature, in order to facilitate couplingbetween the first resin 20 and the second resin 30, which have beenmelted, and the first fabric 10. To this end, respective rollers 310,320, 330, 340, and 350 may have heating wires or the like providedtherein.

In addition, the case manufacturing device 100 according to the presentdisclosure is preferably configured such that the surface temperature ofthe second roller 320 is higher than the surface temperature of thefirst roller 310, the surface temperature of the third roller 330 andthe fourth roller 340 is higher than the surface temperature of thesecond roller 320, and the surface temperature of the fifth roller 350is higher than the surface temperature of the third roller 330 and thefourth roller 340.

For example, the first roller 310 preferably has a surface temperatureof about 70° C.; the second roller 320 preferably has a surfacetemperature of about 75° C.; the third roller 330 and the fourth roller340 preferably have a surface temperature of about 80° C.; and the fifthroller 350 preferably has a surface temperature of about 90° C. Inaddition, the temperatures preferably increase gradually along thedirection in which the multilayer sheet 3 is manufactured (the directionin which the first fabric 10 moves).

Such a configuration for a gradual temperature increase guarantees thatthe first resin 20, the first fabric 10, and the second resin 30 canmaintain at least predetermined levels of temperatures withoutsubstantial temperature decreases while passing through the first roller310, the second roller 320, the third roller 330, the fourth roller 340,and the fifth roller 350. As a result, the first resin 20, the firstfabric 10, and the second resin 30 can be stably coupled to one another(unwanted hardening of the first resin 20 and the second resin can beprevented). In addition, since the surface temperature of the secondroller 320 is slightly higher than the surface temperature of the firstroller 310, a temperature loss resulting from the thickness of the firstfabric 10 can be compensated for such that even ranges of temperaturescan act on both surfaces of the first resin 20.

Meanwhile, at least one of the first resin 20 and the second resin 30may be configured to be transparent. In such a case, the color, texture,and the like of the first fabric 10 can be seen from the outside throughthe first resin 20 and/or the second resin 30. Accordingly, the travelbag 1 can be endowed with a color expression without a separate processfor coloring or the like after the multilayer sheet 3 is manufactured,thereby reducing the manufacturing process and cost, and the shape ofthe first fabric 10 (for example, the woven shape) is naturallyexpressed, thereby improving the completeness of the product (travel bag1).

As described above, in connection with the case manufacturing device 100according to the present disclosure, the first resin 20, the firstfabric 10, and the second resin 30 are coupled to one another whilepassing through the first roller 310, the second roller 320, the thirdroller 330, and the fourth roller (as well as the fifth roller 350),thereby manufacturing a multilayer sheet 3.

After passing through the fourth roller 340 and the fifth roller 350,the multilayer sheet 3 is transferred and cooled, and is then cut into apredetermined size suitable for manufacture of each case 2.

As described above, in connection with manufacturing a case 2 of atravel bag 1 according to the present disclosure, the first resin 20,the first fabric 10, and the second resin 30 are laminated and coupledto one another, and the first resin 20 and the second resin 30 arecoupled to each other via the through-holes 13 of the first fabric 10.Accordingly, the first resin 20 and the second resin 30 are evenlyabsorbed and coated on the surface of the first fabric 10, and the firstresin 20, the first fabric 10, and the second resin 30 are tightlycoupled to one another. As a result, the unique color of the firstfabric 10 can be seen from the outside through the first resin 20 and/orthe second resin 30; it is possible to manufacture a case 2 having veryexcellent compactness, tensile strength, and impact strength; and it ispossible to provide a multilayer sheet 3 and a case 2.

In addition, inclusion of the first fabric 10 made of a combination offibers makes it possible to form a multilayer sheet 3 and a case 2, theoverall tensile strength and impact strength are additionally improved.As will be described later, the ratio of fracture during plasticdefamation can be reduced in the process of press-working the multilayersheet 3 to foam a case 2, and the ratio of defective cases 2manufactured can be decreased.

FIG. 4 schematically illustrates a partial configuration of a casemanufacturing device 100 according to another embodiment of the presentdisclosure. FIG. 5 is an exploded perspective view schematicallyillustrating a multilayer sheet 3 according to another embodiment of thepresent disclosure. FIG. 6 is an exploded perspective view schematicallyillustrating a multilayer sheet 3 according to still another embodimentof the present disclosure.

It is to be noted that, although the multilayer sheet 3 is expressed ina line type in FIG. 4, the multilayer sheet 3 has a width in a directionparallel with the rotating shafts 311, 321, 331, 341, and 351 ofrespective rollers 310, 320, 330, 340, and 350.

FIG. 5 is for the purpose of illustrating the laminated configuration ofthe multilayer sheet 3. The first fabric 10, the second fabric 40, thethird fabric 50, the first resin 20, and the second resin 30 may beconfigured in forms different from those illustrated in FIG. 5, and mayalso have sizes larger than those illustrated in FIG. 5.

The case manufacturing device 100 according to the present disclosureincludes a first fabric supply portion 110, a first resin supply portion210, a first roller 310, a second roller 320, a second resin supplyportion 220, a third roller 330, a fourth roller 340, and a fifth roller350, as described above. In addition, the case manufacturing device 100may further include a second fabric supply portion 120 and a thirdfabric supply portion 130.

Unless specified otherwise, the first fabric supply portion 110, thefirst resin supply portion 210, the first roller 310, the second roller320, the second resin supply portion 220, the third roller 330, thefourth roller 340, the fifth roller 350, the first fabric 10, the firstresin 20, and the second resin 30 may be configured in the same manneras described with reference to FIG. 2 and FIG. 3.

The second fabric supply portion 120 is configured to continuouslysupply a second fabric 40. The second fabric 40 is famed by coupling offibers, and has multiple through-holes 43 that penetrate the fabric.Particularly, the second fabric 40 is configured in a thin cloth typeand has through-holes 43 that penetrate the same from one surface to theother surface thereof. Such through-holes 43 are repeatedly arrangedthroughout the entire area of the second fabric 40.

The second fabric 40 according to the present disclosure may be made ofa woven material, a knitted material, a non-woven fabric, or acombination thereof. Particularly, the second fabric 40 is preferablymade of a woven material.

The material, size, and shape of the second fabric 40 may differ fromthose of the first fabric 10, but are preferably configured in the samemanner. Accordingly, detailed descriptions of the second fabric 40identical to those of the first fabric 10 will be omitted herein.

The second fabric 40 supplied from the second fabric supply portion 120is continuously supplied between the first roller 310 and the secondroller 320 and, after passing between the first roller 310 and thesecond roller 320, moves so as to surround the outer peripheral surfaceof the second roller 320.

It is to be noted that the case manufacturing device 100 according tothe present disclosure is configured such that, in connection withsupplying the second fabric 40 between the first roller 310 and thesecond roller 320, the second fabric 40 is positioned opposite the firstfabric 10 with reference to the first resin 20 such that the secondfabric 40 directly contacts the outer peripheral surface of the firstroller 310, and the first resin 20 is coupled to the second fabric 40and to the first fabric 10 so as to be interposed between the secondfabric 40 and the first fabric 10.

Assuming that the thickness of the first resin 20 discharged from thenozzle of the first resin supply portion 210 is t1, the thickness of thefirst fabric 10 supplied from the first fabric supply portion 110 is t2,the thickness of the second fabric 40 supplied from the second fabricsupply portion 120 is t6, and the gap between the first roller 310 andthe second roller 320 is t3′, t3′ is preferably smaller than the sum oft1, t2 and t6.

The coupling between the second fabric 40 and the first resin 20proceeds in the same manner as that of the coupling between the firstfabric 10 and the first resin 20 described above.

The second fabric 40, the first resin 20, and the first fabric 10 aresuccessively laminated and coupled while passing through the gap betweenthe first roller 310 and the second roller 320, and the same then movein a predetermined range while being forced against the outer peripheralsurface of the second roller 320.

In addition, the surface temperature of the second roller 320 ispreferably identical to the surface temperature of the first roller 310.For example, the surface temperature of the first roller 310 and that ofthe second roller 320 are preferably about 70° C.

The third fabric supply portion 130 is configured to continuously supplya third fabric 50. The third fabric 50 is famed by coupling of fibers,and has multiple through-holes 53 that penetrate the fabric.Particularly, the third fabric 50 is configured in a thin cloth type andhas through-holes 53 that penetrate the same from one surface to theother surface thereof. Such through-holes 53 are repeatedly arrangedthroughout the entire area of the third fabric 50.

The third fabric 50 according to the present disclosure may be made of awoven material, a knitted material, a non-woven fabric, or a combinationthereof. Particularly, the third fabric 50 is preferably made of a wovenmaterial.

The material, size, and shape of the third fabric 50 may differ fromthose of the first fabric 10, but are preferably configured in the samemanner. Accordingly, detailed descriptions of the third fabric 50identical to those of the first fabric 10 will be omitted herein.

The third fabric 50 supplied from the third fabric supply portion 130 iscontinuously supplied between the third roller 330 and the fourth roller340 and, after passing between the third roller 330 and the fourthroller 340, moves so as to surround the outer peripheral surface of thefourth roller 340.

It is to be noted that the case manufacturing device 100 according tothe present disclosure is configured such that, in connection withsupplying the third fabric 50 between the third roller 330 and thefourth roller 340, the third fabric 50 is positioned opposite the firstfabric 10 with reference to the second resin 30 such that the thirdfabric 50 directly contacts the outer peripheral surface of the fourthroller 340, and the second resin 30 is coupled to the first fabric 30and to the third fabric 50 so as to be interposed between the firstfabric 10 and the third fabric 50.

Assuming that the thickness of the first resin 20 discharged from thenozzle of the first resin supply portion 210 is t1, the thickness of thefabric 10 supplied from the first fabric supply portion 110 is t2, thethickness of the second resin 30 discharged from the nozzle of thesecond resin supply portion 220 is t4, the thickness of the secondfabric 40 supplied from the second fabric supply portion 120 is t6, thethickness of the third fabric 50 supplied from the third fabric supplyportion 130 is t7, and the gap between the third roller 330 and thefourth roller 340 is t5′, t5′ is preferably smaller than the sum of t1,t2, t4, t6, and t7.

The coupling between the third fabric 50 and the second resin 30proceeds in the same manner as that of the coupling between the firstfabric 10 and the second resin 30 described above.

The second fabric 40, the first resin 20, the first fabric 10, thesecond resin 30, and the third fabric 50 are successively laminated andcoupled while passing through the gap between the third roller 330 andthe fourth roller 340, and the same then move in a predetermined rangewhile being forced against the outer peripheral surface of the fourthroller 340.

In connection with the case manufacturing device 100 according to thepresent disclosure, as described above, the second fabric 40, the firstresin 20, the first fabric 10, and the second resin 30 are coupled toone another while passing through the first roller 310, the secondroller 320, the third roller 330, and the fourth roller 340 (as well asthe fifth roller 350), thereby manufacturing a multilayer sheet 3.

In addition, the first resin 20, the first fabric 10, the second resin30, and the third fabric 50 are coupled to one another while passingthrough the first roller 310, the second roller 320, the third roller330, and the fourth roller 340 (as well as the fifth roller 350),thereby manufacturing a multilayer sheet 3.

In addition, the second fabric 40, the first resin 20, the first fabric10, the second resin 30, and the third fabric 50 are coupled to oneanother while passing through the first roller 310, the second roller320, the third roller 330, and the fourth roller 340 (as well as thefifth roller 350), thereby manufacturing a multilayer sheet 3.

As such, the multilayer sheet 3 according to the present disclosurefurther includes a second fabric 40 and/or a third fabric 50.Accordingly, it is possible to form a multilayer sheet 3, a case 2, anda travel bag 1 that are more robust, and to foam a product havingexcellent tensile strength and impact strength.

In addition, when the first resin 20 and the second resin 30 areconfigured to be transparent, the second fabric 40 and/or the thirdfabric 50 can overlap with the first fabric 10 and exhibit a uniqueaesthetic appearance. This makes it possible to form a multilayer sheet3, a case 2, and a travel bag 1 with aesthetic appearances.

After passing through the fourth roller 340 and the fifth roller 350,the multilayer sheet 3 is transferred and cooled, and is then cut into apredetermined size suitable for manufacture of each case 2.

Meanwhile, the case manufacturing device 100 according to the presentdisclosure may further include a separate resin supply portion (notillustrated) in addition to the first resin supply portion 210 and thesecond resin supply portion 220. A multilayer sheet 3 manufacturedaccordingly may further include a separate resin layer 60 as illustratedin FIG. 6.

FIG. 7 schematically illustrates a partial configuration of a casemanufacturing device 100 according to the present disclosure.

The case manufacturing device 100 according to the present disclosuremay further include a sheet clamp 400, a preheater 500, and a moldingmachine 600.

After a multilayer sheet 3 is manufactured, a series of continuousmultilayer sheets 3 are cooled and then cut into predetermined sizes,respectively. The multilayer sheets 3 that have been cut intopredetermined sizes are molded into cases 2, respectively. Themultilayer sheets 3 are preferably cut in the shape of quadrangularplates.

The sheet clamp 400 is configured to hold the edge of a multilayer sheet3 and has the shape of a quadrangular frame.

The sheet clamp 400 may be divided into a first clamp 410 and a secondclamp 420. The first clamp 410 and the second clamp 420 may beconfigured as quadrangular frames having the same size and shape, andmay be coupled to each other so as to support the edge of a multilayersheet 3 that has been cut in a quadrangular shape (the edge of aquadrangular multilayer sheet 3 is interposed between the first clamp410 and the second clamp 420).

One corner of each of the first clamp 410 and the second clamp 420 maybe hinge-coupled.

The preheater 500 has multiple slots 510 into which the sheet clamp 400is inserted, and is configured such that a hot wind is supplied andcirculated therein. Particularly, the preheater 500 is configured suchthat multiple multilayer sheets 3 held by sheet clamps 400 can beinserted therein.

The multiple slots 510 of the preheater 500 are arranged to be spacedapart from each other in the leftward/rightward direction, andrespective slots 510 are preferably elongated in the vertical direction.This guarantees that a hot wind efficiently circulates inside thepreheater 500.

In order to circulate a hot wind inside the preheater 500, a boiler anda blower may be formed inside the preheater 500, thereby steadilyheating multiple sheet clamps 400 inserted into the preheater 500.

The multilayer sheets 3 heated inside the preheater 500 are againwithdrawn from the preheater 500 while being held by the sheet clamps400, and are then molded in the shape of cases 2 by the molding machine600.

The molding machine 600 is configured in a conventional press moldingmachine type, and may include a first mold 610 and a second mold 620combined with each other with a multilayer sheet 3 interposed betweenthe same.

Although specific embodiments of the present disclosure have previouslybeen described and illustrated, it would be obvious to a person skilledin the art that the present disclosure is not limited to the describedembodiments, and could be variously changed and modified withoutdeviating from the idea and scope of the present disclosure. Therefore,such examples of changes or modifications are not to be understoodindividually from the technical idea or viewpoint of the presentdisclosure, and modified embodiments fall into the claims of the presentdisclosure.

INDUSTRIAL APPLICABILITY

A multilayer sheet including a fabric and a resin, a case of a travelbag including the sheet, and a device for manufacturing the same,according to the present disclosure, are for the purpose ofmanufacturing a travel bag in a card case type, the strength of whichcan be further improved. Not only the tensile strength and impactstrength of the entire multilayer sheet can be improved substantiallyand become advantageous, the aesthetic appearance and naturalness uniqueto the first fabric can be directly seen from and embedded in themanufactured case. It is possible to provide a travel bag with anexcellent quality even if the manufacturing cost and manufacturingprocess are reduced. Considering this, the present disclosure is beyondthe limits of conventional technologies and, besides uses regardingrelevant technologies, devices to which the present disclosure isapplied have a sufficient potential for commercial availability ormarketing. It would also be obvious that the present disclosure could beimplemented practically. Therefore, the present disclosure has anindustrial applicability.

1. A multilayer sheet constituting a case of a travel bag, the shape ofwhich is made through plastic working such that articles are containedtherein, the multilayer sheet having elastically restoring power andcomprising: a first fabric that comprises a fabric configured bycoupling of fibers and has multiple through-holes penetrating thefabric; a first resin laminated on the first fabric and absorbed andcoated on a surface of the first fabric; and a second resin laminated onthe first fabric from a side opposite to the first resin, absorbed andcoated on the surface of the first fabric, and coupled to the firstresin via the through-holes.
 2. The multilayer sheet as claimed in claim1, comprising: a second fabric that comprises a fabric configured bycoupling of fibers and has multiple through-holes penetrating thefabric, the second fabric being laminated on the first resin from a sideopposite to the first fabric; and a third fabric that comprises a fabricconfigured by coupling of fibers and has multiple through-holespenetrating the fabric, the third fabric being laminated on the secondresin from the side opposite to the first fabric.
 3. The multilayersheet as claimed in claim 1, wherein the first fabric is made of a wovenmaterial, the first fabric, the first resin, and the second resin aremade of polypropylene, and at least one of the first resin and thesecond resin is configured to be transparent.
 4. (canceled)
 5. A case ofa travel bag comprising a multilayer sheet as claimed in claim 1configured by press working.
 6. A case manufacturing device formanufacturing a case of a travel bag, the shape of which is made throughplastic working such that articles are contained therein, the travel baghaving elastically restoring power, the case manufacturing devicecomprising: a first fabric supply portion configured to continuouslysupply a first fabric that comprises a fabric configured by coupling offibers and has multiple through-holes penetrating the fabric; a firstresin supply portion configured to continuously supply a molten firstresin in a directly downward direction; a first roller and a secondroller rotating in opposite directions while constituting a pair suchthat the first fabric and the first resin pass between the first rollerand the second roller and become laminated on each other; a second resinsupply portion configured to continuously supply a molten second resinin a directly downward direction; and a third roller and a fourth rollerrotating in opposite directions while constituting a pair such that thefirst resin, the first fabric, and the second resin pass between thethird roller and the fourth roller and become laminated successively,thereby coupling and combining the first resin and the second resin viathe through-holes.
 7. The case manufacturing device as claimed in claim6, wherein the first roller is configured to directly contact the firstresin; the second roller is configured to directly contact the firstfabric; the third roller is configured to directly contact the firstresin laminated on the first fabric; the fourth roller is configured todirectly contact the second resin; and the first roller, the secondroller, the third roller, and the fourth roller are continuouslyarranged in a row.
 8. The case manufacturing device as claimed in claim7, further comprising a fifth roller arranged adjacent to the fourthroller and configured to rotate in the opposite direction to the fourthroller, wherein the surface temperature of the second roller is higherthan the surface temperature of the first roller, the surfacetemperature of the third roller and the fourth roller is higher than thesurface of the second roller, and the surface temperature of the fifthroller is higher than the surface temperature of the third roller andthe fourth roller.
 9. The case manufacturing device as claimed in claim6, further comprising a second fabric supply portion configured tocontinuously supply a second fabric that comprises a fabric configuredby coupling of fibers and has multiple through-holes penetrating thefabric, wherein the first roller and the second roller are configuredsuch that the second fabric, the first resin, and the first fabric passbetween the first roller and the second roller and become laminatedsuccessively.
 10. The case manufacturing device as claimed in claim 9,further comprising a third fabric supply portion configured tocontinuously supply a third fabric that comprises a fabric configured bycoupling of fibers and has multiple through-holes penetrating thefabric, wherein the third roller and the fourth roller are configuredsuch that the second fabric, the first resin, the first fabric, thesecond resin, and the third fabric between the third roller and thefourth roller and become laminated successively.
 11. The casemanufacturing device as claimed in claim 6, comprising: a sheet clampconfigured to hold an edge of a multilayer sheet comprising the firstresin, the first fabric, and the second resin after passing through thethird roller and the fourth roller; a preheater having multiple slotsinto which the sheet clamp is inserted, the preheater being configuredsuch that a hot wind is supplied and circulated therein; and a moldingmachine configured to press-work the multilayer sheet preheated throughthe preheater, wherein the slots are arranged to be spaced apart fromeach other in a leftward/rightward direction.